The present invention relates to an improved opening and supporting device for a sunshade which is equipped with a rack-like member having a plurality of Z-shaped teeth disposed on the main shaft at a specific section over which the runner of the sunshade travels during the opening and closing of the same. A supporting pin housed in a cavity which is provided with a through hole at the front end thereof on the wall of the groove with a spring received therein is connected to an arc arm pivotally secured to a lug disposed on the outer wall of the runner. The bias spring is disposed between a restraint flange disposed on the front portion of the supporting pin and a lid secured to the open end of the cavity. So the actuation of the arc arm connected to the end of the supporting pin which is led through a through hole on the lid can force the supporting pin to move backward against the bias spring and the release of the arm permits the biased spring to push the supporting pin to travel in a reverse direction so as to let the front tip of the supporting pin to selectively engage with one tooth of the racklike member whereby the runner of the sunshade can be automatically retained in place when it is pushed upwardly open, and can be slidably operated downwardly when the pivot arm is actuated to make the supporting pin withdrawn in the cavity, permitting the runner to move downward.
As shown in FIG. 1, a prior art sunshade is provided with a plurality of locking holes 111 on the main shaft 11 thereof on which a runner 12 is slidably located. A plurality of supporting ribs 13 are pivotally connected to the runner at one end and connected to the middle of the frame ribs 14 at the other end so that the upward sliding of the runner will push the sunshade open, and the downward movement of the same will make the sunshade collapse. A top cover 15 is attached to the frame of the sunshade. A supporting pin 132 attached to a chain 131 at one end which is secured to one of the supporting ribs 13 is used to retain the runner 12 in place when the supporting pin 132 is selectively engaged with one of the locking holes 111 with the runner located just above the supporting pin 132 and supported in place by the same.
To collapse the sunshade 1, an operator only has to reverse the steps cited above so as to permit the runner 12, free of the retaining of the supporting pin 132, to move downwardly.
Generally speaking, the conventional sunshade opening device using a supporting pin is able to be operated with ease, but there are still some disadvantages associated therewith in practical operation, which are given as follows:
1. The size of the sunshade is usually very large so that it can keep a wide area covered; the larger the sunshade is the heavier it becomes; an operator has to push the runner upwardly with great effort first with hands and then hold the runner in place with one hand and locate the supporting pin with the other; and the supporting pin is selectively inserted into one of the locking holes as long as the runner is disposed at a desired position and the supporting pin is in alignment with the target locking hole. If not, the operator has to make some adjustments of the location of the runner and the supporting pin. To an operator who is too weak to open the heavy sunshade with one hand, the opening of the same without help from others becomes impossible, causing great inconvenience in practical operation.
2. The main shaft and the runner of the sunshade are slidably engaged with each other and the two are usually assembled together in a loose manner so that the runner can be smoothly moved; but the loose engagement of the runner with the main shaft produces crevice therebetween which can get the fingers of an operator hurt easily when the skin of the fingers is accidentally clamped in the crevice in the collapse of the sunshade.
To overcome the above cited problems, the present inventor has worked out an improved opening and supporting device for a sunshade which is presented in details in the following description along with a number of drawings.